The Sonnet Cycle, "Dreams from R'lyeh", that comprises the first two-thirds of the book, consists of poems inspired by H. P. Lovecraft and the Cthulhu Mythos. Unlike Lovecraft's Fungi from Yuggoth, the sonnets of which do not tell a continuous story, Dreams from R'lyeh from start to finish clearly narrates the story of Wilbur Nathaniel Hoag, from his childhood to just before his disappearance in late 1944. Mental (and perhaps physical) degeneration are apparent near the last sonnet.

The remainder of the verses are on various topics, celebrating other fantasy authors or reflecting on fantastic themes. "Diombar's Song of the Last Battle" is a heroic poem set in the prehistory of Carter's "Thongor" novels, and "Death-Song of Conan the Cimmerian" an end-of-life summation of Robert E. Howard's barbarian hero Conan, written from the perspective of the character himself.